text: import RPi.GPIO as GPIO
  import time
  
  #5V(red) -> pin 4
  #GND(black) -> pin 6
  #servo motor -> pin 11 (GPIO17)
  
  servoPIN = 11
  
  GPIO.setmode(GPIO.BOARD)
  
  GPIO.setup(servoPIN, GPIO.OUT)
  
  p = GPIO.PWM(servoPIN, 50)
  
  #servo having 20ms cycles, dc=0.5/20 X100 = 2.5% ->90degree
  
  p.start(5) #initialization, 0degree
  
  try:
      while True:
          p.ChangeDutyCycle(7.5)  # turn towards 90 degree
          time.sleep(1) # sleep 1 second
          p.ChangeDutyCycle(5)  # turn towards 0 degree
          time.sleep(1) # sleep 1 second
          p.ChangeDutyCycle(10) # turn towards 180 degree
          time.sleep(1) # sleep 1 second 
  
  except KeyboardInterrupt:
      p.stop()
      GPIO.cleanup()